borg importer

README.rst

@@ -18,6 +18,17 @@ Note: we have different importers and some importers may not support all the fea
 Currently supported import formats
 ==================================
 
+`BorgBackup <https://github.com/borgbackup/borg>`_
+--------------------------------------------------
+
+Imports archives from an existing Borg repository into a new one.
+This is useful when a Borg repository needs to be rebuilt (e.g. if
+your borg key and passphrase was compromised).
+
+Usage: ``borg-import borg SOURCE_REPOSITORY DESTINATION_REPOSITORY``
+
+See ``borg-import borg -h`` for help.
+
 `rsnapshot <https://github.com/rsnapshot/rsnapshot>`_
 -----------------------------------------------------
 

docs/usage.rst

@@ -24,3 +24,10 @@ borg-import rsnapshot
 ---------------------
 
 .. generate-usage:: rsnapshot
+
+.. _borg:
+
+borg-import borg
+----------------
+
+.. generate-usage:: borg

pyproject.toml

@@ -49,17 +49,14 @@ write_to = "src/borg_import/_version.py"
 python_files = "testsuite/*.py"
 testpaths = ["src"]
 
-[tool.pytest.ini_options]
-addopts = "-rs --cov=borg_import --cov-config=pyproject.toml"
-
 [tool.flake8]
 max-line-length = 120
 exclude = "build,dist,.git,.idea,.cache,.tox,docs/conf.py,.eggs"
 
 [tool.coverage.run]
 branch = true
 source = ["src/borg_import"]
-omit = ["*/borg_import/helpers/testsuite/*"]
+omit = ["*/borg_import/helpers/testsuite/*", "*/borg_import/testsuite/*"]
 
 [tool.coverage.report]
 exclude_lines = [
@@ -77,15 +74,14 @@ env_list = ["py39", "py310", "py311", "py312", "py313", "flake8"]
 
 [tool.tox.env_run_base]
 package = "editable-legacy"
+commands = [["pytest", "-v", "-rs", "--cov=borg_import", "--cov-config=pyproject.toml", "--pyargs", "{posargs:borg_import}"]]
+deps = ["-rrequirements.d/development.txt"]
 passenv = ["*"]
 
 [tool.tox.env_pkg_base]
 passenv = ["*"]
 
-[tool.tox.env.testenv]
-deps = ["-rrequirements.d/development.txt"]
-commands = [["pytest", "-rs", "--cov=borg_import", "--cov-config=pyproject.toml", "--pyargs={posargs:borg_import.helpers.testsuite}"]]
+[tool.tox.env."py{39,310,311,312,313}"]
 
 [tool.tox.env.flake8]
-deps = ["flake8-pyproject"]
 commands = [["flake8"]]

requirements.d/development.txt

@@ -2,3 +2,4 @@ virtualenv
 tox
 pytest
 pytest-cov
+flake8-pyproject

src/borg_import/borg.py

@@ -0,0 +1,25 @@
+import subprocess
+
+from .helpers.timestamps import datetime_from_string
+
+
+def get_borg_archives(repository):
+    """Get all archive metadata discovered in the Borg repository."""
+    # Get list of archives with their timestamps
+    borg_cmdline = ['borg', 'list', '--format', '{name}{TAB}{time}{NL}', repository]
+    output = subprocess.check_output(borg_cmdline).decode()
+
+    for line in output.splitlines():
+        if not line.strip():
+            continue
+
+        parts = line.split('\t', 1)
+        if len(parts) == 2:
+            name, timestamp_str = parts
+            timestamp = datetime_from_string(timestamp_str)
+            meta = dict(
+                name=name,
+                timestamp=timestamp,
+                original_repository=repository,
+            )
+            yield meta

src/borg_import/helpers/timestamps.py

@@ -32,6 +32,8 @@ def datetime_from_string(s):
             '%Y-%m-%d %H:%M',
             # date tool output [C / en_US locale]:
             '%a %b %d %H:%M:%S %Z %Y',
+            # borg format with day of week
+            '%a, %Y-%m-%d %H:%M:%S',
             # rsync-time-backup format
             '%Y-%m-%d-%H%M%S'
             # for more, see https://xkcd.com/1179/

src/borg_import/main.py

@@ -1,5 +1,6 @@
 import argparse
 import logging
+import os
 import shutil
 import shlex
 import subprocess
@@ -10,12 +11,13 @@
 from .rsnapshots import get_snapshots
 from .rsynchl import get_rsyncsnapshots
 from .rsync_tmbackup import get_tmbackup_snapshots
+from .borg import get_borg_archives
 
 log = logging.getLogger(__name__)
 
 
 def borg_import(args, archive_name, path, timestamp=None):
-    borg_cmdline = ['borg', 'create']
+    borg_cmdline = ['borg', 'create', '--numeric-ids', '--files-cache=mtime,size']
     if timestamp:
         borg_cmdline += '--timestamp', timestamp.isoformat()
     if args.create_options:
@@ -282,6 +284,87 @@ def import_rsync_tmbackup(self, args):
                 import_journal.unlink()
 
 
+class borgImporter(Importer):
+    name = 'borg'
+    description = 'import archives from another Borg repository'
+    epilog = """
+    Imports archives from an existing Borg repository into a new one.
+
+    This is useful when a Borg repository needs to be rebuilt and all archives
+    transferred from the old repository to a new one.
+
+    The importer extracts each archive from the source repository to a intermediate
+    directory inside the current work directory (make sure there is enough space!)
+    and then creates a new archive with the same name and timestamp in the destination
+    repository.
+
+    Because the importer changes the current directory while importing archives,
+    you need to give either absolute paths for the source and destination repositories
+    or ssh:// URLs.
+
+    To avoid issues with user/group id-to-name mappings, the importer will only
+    transfer the numeric user and group ids for the files inside the archives.
+
+    By default, archive names are preserved. Use --prefix to add a prefix to
+    the imported archive names.
+    """
+
+    def populate_parser(self, parser):
+        parser.add_argument('source_repository', metavar='SOURCE_REPOSITORY',
+                            help='Source Borg repository (must be a valid Borg repository spec)')
+        parser.add_argument('repository', metavar='DESTINATION_REPOSITORY',
+                            help='Destination Borg repository (must be a valid Borg repository spec)')
+        parser.set_defaults(function=self.import_borg)
+
+    def import_borg(self, args):
+        existing_archives = list_borg_archives(args)
+
+        # Create a fixed unique directory inside the current working directory
+        import_path = Path.cwd() / f"borg_import_{os.getpid()}"
+        import_path.mkdir(exist_ok=True)
+
+        try:
+            for archive in get_borg_archives(args.source_repository):
+                name = archive['name']
+                timestamp = archive['timestamp'].replace(microsecond=0)
+                archive_name = args.prefix + name
+
+                if archive_name in existing_archives:
+                    print('Skipping (already exists in repository):', name)
+                    continue
+
+                print('Importing {} (timestamp {}) '.format(name, timestamp), end='')
+                if archive_name != name:
+                    print('as', archive_name)
+                else:
+                    print()
+
+                try:
+                    # Extract the archive from the source repository
+                    extract_cmdline = ['borg', 'extract', '--numeric-ids']
+                    extract_cmdline.append(args.source_repository + '::' + name)
+
+                    print('  Extracting archive to import directory...')
+                    subprocess.check_call(extract_cmdline, cwd=str(import_path))
+
+                    # Create a new archive in the destination repository
+                    borg_import(args, archive_name, str(import_path), timestamp=timestamp)
+
+                    # Empty the directory after importing the archive
+                    print('  Cleaning import directory...')
+                    shutil.rmtree(import_path)
+                    import_path.mkdir(exist_ok=True)
+
+                except subprocess.CalledProcessError as cpe:
+                    print('Error during import of {}: {}'.format(name, cpe))
+                    if cpe.returncode != 1:  # Borg returns 1 for warnings
+                        raise
+        finally:
+            # Clean up the import directory when done
+            if import_path.exists():
+                shutil.rmtree(import_path)
+
+
 def build_parser():
     common_parser = argparse.ArgumentParser(add_help=False)
     common_group = common_parser.add_argument_group('Common options')

src/borg_import/testsuite/test_borg.py

@@ -0,0 +1,78 @@
+import subprocess
+
+from borg_import.main import main
+
+
+def test_borg_import(tmpdir, monkeypatch):
+    """Test the borg importer by creating archives in a source repo and importing them to a target repo."""
+    # Create source and target repository directories
+    source_repo = tmpdir.mkdir("source_repo")
+    target_repo = tmpdir.mkdir("target_repo")
+
+    # Create test data directories
+    test_data = tmpdir.mkdir("test_data")
+    archive1_data = test_data.mkdir("archive1")
+    archive2_data = test_data.mkdir("archive2")
+
+    # Create some test files in the archive directories
+    archive1_data.join("file1.txt").write("This is file 1 in archive 1")
+    archive1_data.join("file2.txt").write("This is file 2 in archive 1")
+    archive2_data.join("file1.txt").write("This is file 1 in archive 2")
+    archive2_data.join("file2.txt").write("This is file 2 in archive 2")
+
+    # Initialize the source repository
+    subprocess.check_call(["borg", "init", "--encryption=none", str(source_repo)])
+
+    # Create archives in the source repository
+    subprocess.check_call([
+        "borg", "create",
+        f"{source_repo}::archive1",
+        "."
+    ], cwd=str(archive1_data))
+
+    subprocess.check_call([
+        "borg", "create",
+        f"{source_repo}::archive2",
+        "."
+    ], cwd=str(archive2_data))
+
+    # Initialize the target repository
+    subprocess.check_call(["borg", "init", "--encryption=none", str(target_repo)])
+
+    # Set up command line arguments for borg-import
+    monkeypatch.setattr("sys.argv", [
+        "borg-import",
+        "borg",
+        str(source_repo),
+        str(target_repo)
+    ])
+
+    # Run the borg-import command
+    main()
+
+    # Verify that the archives were imported to the target repository
+    output = subprocess.check_output(["borg", "list", "--short", str(target_repo)]).decode()
+    archives = output.splitlines()
+
+    assert "archive1" in archives
+    assert "archive2" in archives
+
+    # Extract the archives from the target repository and verify their contents
+    extract_dir1 = tmpdir.mkdir("extract1")
+    extract_dir2 = tmpdir.mkdir("extract2")
+
+    subprocess.check_call([
+        "borg", "extract",
+        f"{target_repo}::archive1"
+    ], cwd=str(extract_dir1))
+
+    subprocess.check_call([
+        "borg", "extract",
+        f"{target_repo}::archive2"
+    ], cwd=str(extract_dir2))
+
+    # Verify the contents of the extracted archives
+    assert extract_dir1.join("file1.txt").read() == "This is file 1 in archive 1"
+    assert extract_dir1.join("file2.txt").read() == "This is file 2 in archive 1"
+    assert extract_dir2.join("file1.txt").read() == "This is file 1 in archive 2"
+    assert extract_dir2.join("file2.txt").read() == "This is file 2 in archive 2"